RELATIONSHIP BETWEEN IMMUNE-SYSTEM AND GRAM-NEGATIVE BACTERIA .1. SPONTANEOUS BINDING OF SMOOTH AND ROUGH SALMONELLA TO HUMAN PERIPHERAL-BLOOD LYMPHOCYTES

  • 1 January 1984
    • journal article
    • research article
    • Vol. 58  (1) , 167-173
Abstract
Over the past years many reports have emphasized that either gram-positive or gram-negative bacteria possess the ability to bind spontaneously to human peripheral blood lymphocytes (PBL). Here, bacterial binding to human PBL was studied by using a smooth (S) S. typhimurium LT-2 and 2 rough (R) mutants of S. minnesota R 345 (Rb) and R 595 (Re), which possess specific deletions in their lipopolysaccharide (LPS) molecule. Apparently, all 3 bacterial strains spontaneously bind to PBL, even though Re and mostly Rb cells display the highest degree of adherence. The 3 major regions of LPS (O-polysaccharide chain, R core and lipid A) seem to be involved in the binding since adherence is specifically inhibited by pretreating PBL with S- or R-LPS extracted from homologous bacteria. Using a panel of monoclonal antibodies to lymphocyte surface antigens, S- and R-Salmonella bacteria bind to T lymphocytes (preferentially T8+ cells), while few B cells are coated by bacteria. Bacterial binding is significantly reduced by trypsin pretreatment of PBL, this suggesting that proteins (or glycoproteins) of the PBL membrane are involved in the binding.